Hannover 2010 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
A: Fachverband Atomphysik
A 28: Attosecond Physics II / Interaction with Strong or Short Laser Pulses III
A 28.1: Vortrag
Freitag, 12. März 2010, 14:00–14:15, F 107
Calibration of a High Harmonic Spectrometer by Laser Induced Plasma Emission — •Markus Gühr1,2, Joseph P. Farrell1,2, Brian K. McFarland1,2, and Philip H. Bucksbaum1,2 — 1Stanford PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, USA — 2Physics and Applied Physics, Stanford University, USA
We present a method that allows for a convenient switching between high harmonic generation (HHG) and accurate calibration of the vacuum ultraviolet (VUV) spectrometer used to analyze the harmonic spectrum. The accurate calibration of HHG spectra is becoming increasingly important for the determination of electronic structures. However, the wavelength of the laser harmonics themselves depend on the details of the harmonic geometry and phase matching, making them unsuitable for calibration purposes. In our calibration mode, the target resides directly at the focus of the laser, thereby enhancing plasma emission and suppressing harmonic generation. In HHG spectroscopy mode, the source medium resides in front or after the focus, showing enhanced HHG and no plasma emission lines. The plasma lines can be used for calibrating the spectrometer and we achieve an accuracy of 0.1 nm, which is more than an order of magnitude more accurate than a calibration using the harmonics [1].
[1] J. P. Farrell, B. K. McFarland, P. H. Bucksbaum and M. Gühr, Optics Express, 17, 15142 (2009)